When you have to count your chain first, make sure that you are on the front side. Then count every “V” in your chain; each V is a stitch. If you have problems identify the stitches or the “V’s”, here is an image showing you every countable stitch.
The idea is the same, you have to count the “V’s” but this time they will be on top of the row.
If it’s too difficult for you to identify the stitches from the front when working in rows, you can look at your work from above, and count the “V’s” like in the chain.
Just be careful with the first and last stitch, because sometimes (depending on the thickness of the yarn), you can miss one stitch. stitch markers